Posttraumatic Stress Disorder and the Associated Risk of Autoimmune Skin Diseases: A Nationwide Population-Based Cohort Study

OBJECTIVE: Posttraumatic stress disorder (PTSD) is known as a risk factor for various immune-related disorders; however, the association between PTSD and related autoimmune skin diseases (ASDs) remains unclear. This study aimed to investigate the association of PTSD with the risk of related ASDs. METHODS: Participants were recruited from the National Health Insurance Research Database in Taiwan. We included 9801 patients with PTSD and 39,204 matched controls to assess the risk of developing ASDs. Cox regression model was used for analyses. RESULTS: After adjusting for confounders, we found an increased risk of ASDs among the patients with PTSD (adjusted hazard ratio [aHR] = 3.00, 95% confidence interval [CI] = 2.21-4.07) compared with that among matched controls. Statistically significant associations were found between PTSD and five individual ASDs, including psoriasis (aHR = 3.81, 95% CI = 1.90-7.67), lichen planus (aHR = 31.63, 95% CI = 4.00-249.91), alopecia areata (aHR = 4.77, 95% CI = 2.47-9.20), autoimmune bullous diseases (aHR = 9.55, 95% CI = 1.98-45.99), and vitiligo (aHR = 16.06, 95% CI = 4.48-57.54). CONCLUSIONS: Patients with PTSD had an increased risk of developing ASDs compared with the matched controls. Further studies are needed for better understanding of the underlying mechanisms.